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Martin Jansen

Publications and source records attributed to Martin Jansen.

58 records · Page 4Linked to original sources

Immunoadsorption and plasma exchange in pregnancy.

BACKGROUND: During pregnancy, familial hyperlipidemia or systemic lupus erythematosus (SLE) can exacerbate having devastating consequences for both mother and fetus. Immunoadsorption is established for removal of pathogenic proteins lipoproteins or autoantibodies, but this procedure has only rarely been used in pregnancy. METHODS: We evaluated retrospectively 126 extracorporeal treatments during six pregnancies. Forty low-density lipoprotein immunoadsorptions, 6 sole plasma exchanges and 36 combined procedures (plasma exchange followed by immunoadsorption) were performed for severe hypertriglyceridemia, complicated by acute pancreatitis. Forty-four IgG immunoadsorptions were executed in 2 pregnant women suffering from SLE with a disastrous course during prior pregnancies. RESULTS: In hyperlipidemic pregnant women, mean triglyceride levels prior to treatment were 3,841 +/- 2,076 mg/dl (mean +/- SD) and total cholesterol was 617 +/- 354 mg/dl. Until delivery, a 27% reduction of triglycerides could be achieved. Clinical and serological signs of pancreatitis disappeared after initiation of extracorporeal therapy. Four healthy babies were delivered (birthweights between 2,250 and 3,360 g). In 1 woman suffering from SLE, intrauterine fetal death occurred in the 22nd week of gestation despite a reduction of cardiolipin antibodies by 69%. The second case (a twin pregnancy) was complicated by steroid-resistant antibody-mediated anemia. Due to frequent immunoadsorptions, red blood cell count improved (reduction of antierythrocyte antibodies by 66.6%) and 2 healthy babies (birthweights 2,120 and 2,350 g) were delivered by cesarean section. CONCLUSION: Long-term antibody-based immunoadsorption has been demonstrated to be safe and well tolerated in pregnant women and enables normal intrauterine/fetal development. Although rarely indicated during pregnancy, this treatment modality might be a promising new technique for removal of autoantibodies and lipoproteins in patients with serious gestational complications without sufficient response to conventional therapy.

Adsorption↗

Structural relationships between cations and alloys; an equivalence between oxidation and pressure.

More than 100 examples are provided of the structural identity between the cation arrays in oxides and their corresponding alloys (binary compounds). Halides and halogenates, sulfides and sulfites and/or sulfates, selenides and selenates, phosphides and phosphates show this behaviour. In some cases, the structure of the cation subarray corresponds to the structure of the alloy at ambient conditions, but in other cases, cations stabilize structures which correspond to those of the high-pressure phases of the alloy, from which an analogy between the insertion of oxygen and the application of pressure can be established. In this last case, the oxides show polymorphism with temperature and when heated, the structure of the ambient pressure of the alloy is recovered as if heating would compensate the effect of pressure. From the results reported here, it is concluded that cations do not seem to be either the isolated entities, predicted by the ionic model, which occupy interstices of an oxygen matrix, or they arrange in a more or less arbitrary way, but they try to reproduce the structure of their corresponding alloy. Many of the phase transitions and the polymorphism exhibited by the oxides described here are better explained when they are considered as formed by previous entities which are the alloys. Oxides should be considered as 'real stuffed alloys'. These features do not seem to be casual, but they obey a general principle: Cations recognize themselves in spite of being embedded in an oxygen bulk. The nature and the physical meaning of this recognition are problems which remain unsolved.

Journal Article↗